Malaria parasites use a soluble RhopH complex for erythrocyte invasion and an integral form for nutrient uptake

  1. Marc A Schureck
  2. Joseph E Darling
  3. Alan Merk
  4. Jinfeng Shao
  5. Geervani Daggupati
  6. Prakash Srinivasan
  7. Paul D B Olinares
  8. Michael P Rout
  9. Brian T Chait
  10. Kurt Wollenberg
  11. Sriram Subramaniam
  12. Sanjay A Desai  Is a corresponding author
  1. National Institute of Allergy and Infectious Diseases, National Institutes of Health, United States
  2. National Cancer Institute, NIH, United States
  3. Johns Hopkins Bloomberg School of Public Health, United States
  4. The Rockefeller University, United States
  5. University of British Columbia, Canada

Abstract

Malaria parasites use the RhopH complex for erythrocyte invasion and channel-mediated nutrient uptake. As the member proteins are unique to Plasmodium spp., how they interact and traffic through subcellular sites to serve these essential functions is unknown. We show that RhopH is synthesized as a soluble complex of CLAG3, RhopH2, and RhopH3 with 1:1:1 stoichiometry. After transfer to a new host cell, the complex crosses a vacuolar membrane surrounding the intracellular parasite and becomes integral to the erythrocyte membrane through a PTEX translocon-dependent process. We present a 2.9 Å single-particle cryo-electron microscopy structure of the trafficking complex, revealing that CLAG3 interacts with the other subunits over large surface areas. This soluble complex is tightly assembled with extensive disulfide bonding and predicted transmembrane helices shielded. We propose a large protein complex stabilized for trafficking but poised for host membrane insertion through large-scale rearrangements, paralleling smaller two-state pore-forming proteins in other organisms.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files. Cryo-EM maps have been deposited in EMDB and PDB.

Article and author information

Author details

  1. Marc A Schureck

    Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, United States
    Competing interests
    No competing interests declared.
  2. Joseph E Darling

    Laboratory of Cell Biology, National Cancer Institute, NIH, Bethesda, United States
    Competing interests
    No competing interests declared.
  3. Alan Merk

    Laboratory of Cell Biology, National Cancer Institute, NIH, Bethesda, United States
    Competing interests
    No competing interests declared.
  4. Jinfeng Shao

    Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, United States
    Competing interests
    No competing interests declared.
  5. Geervani Daggupati

    Department of Molecular Microbiology and Immunology, and Johns Hopkins Malaria Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, United States
    Competing interests
    No competing interests declared.
  6. Prakash Srinivasan

    Department of Molecular Microbiology and Immunology, and Johns Hopkins Malaria Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, United States
    Competing interests
    No competing interests declared.
  7. Paul D B Olinares

    Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, United States
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3429-6618
  8. Michael P Rout

    Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, United States
    Competing interests
    No competing interests declared.
  9. Brian T Chait

    Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, United States
    Competing interests
    No competing interests declared.
  10. Kurt Wollenberg

    Office of Cyber Infrastructure & Computational Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, United States
    Competing interests
    No competing interests declared.
  11. Sriram Subramaniam

    Urological Sciences, University of British Columbia, Vancouver, Canada
    Competing interests
    Sriram Subramaniam, Reviewing editor, eLife.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4231-4115
  12. Sanjay A Desai

    Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, United States
    For correspondence
    sdesai@niaid.nih.gov
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2150-2483

Funding

National Institute of Allergy and Infectious Diseases

  • Sanjay A Desai

National Cancer Institute

  • Sriram Subramaniam

National Institutes of Health (P41 GM103314)

  • Brian T Chait

National Institutes of Health (P41 GM109824)

  • Michael P Rout
  • Brian T Chait

Canada Excellence Research Chairs, Government of Canada

  • Sriram Subramaniam

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Copyright

This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.

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  1. Marc A Schureck
  2. Joseph E Darling
  3. Alan Merk
  4. Jinfeng Shao
  5. Geervani Daggupati
  6. Prakash Srinivasan
  7. Paul D B Olinares
  8. Michael P Rout
  9. Brian T Chait
  10. Kurt Wollenberg
  11. Sriram Subramaniam
  12. Sanjay A Desai
(2021)
Malaria parasites use a soluble RhopH complex for erythrocyte invasion and an integral form for nutrient uptake
eLife 10:e65282.
https://doi.org/10.7554/eLife.65282

Share this article

https://doi.org/10.7554/eLife.65282

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